# 2008 August 29

 #

 # The author disclaims copyright to this source code.  In place of

 # a legal notice, here is a blessing:

 #

 #    May you do good and not evil.

 #    May you find forgiveness for yourself and forgive others.

 #    May you share freely, never taking more than you give.

 #

 #***********************************************************************

 #

 # This file is focused on testing the pcache module.

 #

 # $Id: pcache.test,v 1.2 2008/09/05 05:29:09 danielk1977 Exp $

 set testdir [file dirname $argv0]

 source $testdir/tester.tcl

 # The pcache module limits the number of pages available to purgeable

 # caches to the sum of the 'cache_size' values for the set of open

 # caches. This block of tests, pcache-1.*, test that the library behaves

 # corrctly when it is forced to exceed this limit.

 #

 do_test pcache-1.1 {

   db close

   pcache_stats

 } {current 0 max 0 min 0 recyclable 0}

 do_test pcache-1.2 {

   sqlite3 db test.db

   execsql {

     PRAGMA cache_size=10;

     PRAGMA auto_vacuum=0;

   }

   pcache_stats

 } {current 1 max 10 min 10 recyclable 1}

 do_test pcache-1.3 {

   execsql {

     BEGIN;

     CREATE TABLE t1(a, b, c);

     CREATE TABLE t2(a, b, c);

     CREATE TABLE t3(a, b, c);

     CREATE TABLE t4(a, b, c);

     CREATE TABLE t5(a, b, c);

   }

   pcache_stats

 } {current 6 max 10 min 10 recyclable 0}

 do_test pcache-1.4 {

   execsql {

     CREATE TABLE t6(a, b, c);

     CREATE TABLE t7(a, b, c);

     CREATE TABLE t8(a, b, c);

     CREATE TABLE t9(a, b, c);

   }

   pcache_stats

 } {current 10 max 10 min 10 recyclable 0}

 do_test pcache-1.5 {

   sqlite3 db2 test.db

   execsql "PRAGMA cache_size=10" db2

   pcache_stats

 } {current 11 max 20 min 20 recyclable 1}

 do_test pcache-1.6 {

   execsql {

     BEGIN;

     SELECT * FROM sqlite_master;

   } db2

   pcache_stats

 } {current 11 max 20 min 20 recyclable 0}

 # At this point connection db2 has a read lock on the database file and a 

 # single pinned page in its cache. Connection [db] is holding 10 dirty 

 # pages. It cannot recycle them because of the read lock held by db2.

 #

 do_test pcache-1.6 {

   execsql {

     CREATE INDEX i1 ON t1(a, b);

     CREATE INDEX i2 ON t2(a, b);

     CREATE INDEX i3 ON t3(a, b);

     CREATE INDEX i4 ON t4(a, b);

     CREATE INDEX i5 ON t5(a, b);

     CREATE INDEX i6 ON t6(a, b);

     CREATE INDEX i7 ON t7(a, b);

     CREATE INDEX i8 ON t8(a, b);

     CREATE INDEX i9 ON t9(a, b);

   } 

   pcache_stats

 } {current 20 max 20 min 20 recyclable 0}

 do_test pcache-1.7 {

   execsql {

     CREATE TABLE t10(a, b, c);

   } 

   pcache_stats

 } {current 21 max 20 min 20 recyclable 0}

 # Rolling back the transaction held by db2 at this point releases a pinned

 # page. Because the number of allocated pages is greater than the 

 # configured maximum, this page should be freed immediately instead of

 # recycled.

 #

 do_test pcache-1.8 {

   execsql {ROLLBACK} db2

   pcache_stats

 } {current 20 max 20 min 20 recyclable 0}

 do_test pcache-1.9 {

   execsql COMMIT

   pcache_stats

 } {current 20 max 20 min 20 recyclable 20}

 do_test pcache-1.10 {

   db2 close

   pcache_stats

 } {current 10 max 10 min 10 recyclable 10}

 do_test pcache-1.11 {

   execsql { PRAGMA cache_size = 20 }

   pcache_stats

 } {current 10 max 20 min 10 recyclable 10}

 do_test pcache-1.12 {

   execsql { 

     SELECT * FROM t1 ORDER BY a; SELECT * FROM t1;

     SELECT * FROM t2 ORDER BY a; SELECT * FROM t2;

     SELECT * FROM t3 ORDER BY a; SELECT * FROM t3;

     SELECT * FROM t4 ORDER BY a; SELECT * FROM t4;

     SELECT * FROM t5 ORDER BY a; SELECT * FROM t5;

     SELECT * FROM t6 ORDER BY a; SELECT * FROM t6;

     SELECT * FROM t7 ORDER BY a; SELECT * FROM t7;

     SELECT * FROM t8 ORDER BY a; SELECT * FROM t8;

     SELECT * FROM t9 ORDER BY a; SELECT * FROM t9;

   }

   pcache_stats

 } {current 19 max 20 min 10 recyclable 19}

 do_test pcache-1.13 {

   execsql { PRAGMA cache_size = 15 }

   pcache_stats

 } {current 15 max 15 min 10 recyclable 15}

 finish_test